Self-lubricating pin

A pin pivotably coupling a clevis arm to a lug of a second element, the pin comprising:

• a hollow cylindrical body with a first end cap coupled to a first end of the body and a second end cap coupled to a second end of the body, the body and the first and second end caps at least partially defining a cavity within the body, one of the first and second ends including an annular flange extending radially therefrom for seating against a first clevis arm lug, the other of the first and second ends including external threads formed thereon for receiving a nut which abuts a second clevis arm lug, the pin extending through aligned apertures in the first and second clevis arm lugs and the lug of the second element disposed therebetween;
• a piston slidably disposed within the cavity and dividing the cavity into a first chamber proximate to the first end and a second chamber proximate to the second end, wherein at least one aperture extends through the body and is in fluid communication with the first chamber, and the second chamber is fluidly isolated from an environment around the body;
• a valve comprising a standard grease fitting mounted to an aperture formed in the first end cap and fixedly positioned relative to the body, wherein the valve is configured to selectively provide a path to fill the first chamber with lubricant;
• a seal mounted to an aperture formed in the second end cap and configured to be removed selectively to enable fluid communication between the second chamber and the environment around the body;
• and
• a lubricant disposed within the first chamber,
• wherein, when a pressure in the second chamber is greater than a pressure of the environment, the piston moves within the cavity toward the first end of the body, and
• wherein movement of the piston toward the first end of the body discharges lubricant through the at least one aperture.